Rig mat systems of this general type are shown in Canadian Patents No: 2,348,328 issued Oct. 22, 2002 and 2,364,968 issued Jun. 22, 2004 both to David and James Stasiewich.
Another arrangement is shown in U.S. Pat. No. 7,160,055 of Beamish issued Jan. 9, 2007.
These all provide arrangements for connecting the panels each to the next to integrate the structure so that the panels do not separate as the heavy vehicles pass over.
However these arrangements are not entirely suitable leaving opportunity for an improved system of connecting the panels end to end.
The panels used can be of the type described below or may be of other constructions. However the mounting arrangement is particularly designed for use with the panels described herein.
A number of prior proposals have been made for manufacturing a composite core panel formed from a honeycomb panel formed with tubular cells at right angles to the panel where the panel is filled with a reinforcing foam extending through the cells so as to provide an enhanced compression strength of the core in a direction longitudinally of the cells. This strength is commonly significantly greater than the compression strength of the core and the foam separately. The core panel is then covered on top and bottom by reinforcing sheets of a fibrous reinforcing material which are then resin filled by a resin impregnation process, for example infusion, so as to attach the top and bottom sheets to the foam and honeycomb core panel. The compression strength of the core panel has a direct relationship to the shear strength of the finished panel so that it has been desirable to maximize this compression strength. Such panels have become widely used for many products.
The materials commonly used for the honeycomb panel are phenolic paper, aluminum and various types of plastic materials. The selection is made in part dependent on cost relative to the desired strength with the aluminum of course providing the highest strength at the highest cost. Phenolic paper is the simplest and cheapest option and is very widely used. The honeycomb, in many cases, is formed by bonding strips side by side with the tubular cells formed around rods or simply by stretching the bonded strips longitudinally of the panel to open them up. Adhesive and heat sealing can be used for attaching the strips.
However there is always an ongoing requirement for yet further increasing the strength of such panels to enable additional markets to be entered or for strength requirements to be met with a thinner panel of less material.